柴油机振动信号的分形特征及故障诊断

把小波包降噪与关联维数相结合用在柴油机故障诊断中，讨论了关联维数计算中相关参数的选取。首先对柴油机缸盖振动信号进行小波包降噪处理，通过自相关函数法求延迟时间，用饱和关联维数法确定最小嵌入维数，并用改进的G-P算法求关联维数。分析发现，小波包可以有效降低噪声干扰，柴油机在不同工况下具有不同的关联维数，该方法可有效应用于柴油机的故障诊断中。

Fractal Characteristics and Fault Diagnosis of Vibration Signal of Diesel Engines

Having research the application of the wavelet packet de-noising and correlation dimension in fault diagnosis of diesel engine, discussing the selection of related parameters in the calculation of correlation dimension. The wavelet packet de-noising processes the engine vibration signal firstly , then the autocorrelation function method for time delay, saturation correlation dimension method to determine the minimum embedding dimension, the improved G-P algorithm to calculate the correlation dimension. The analysis shows, wavelet packet can effectively reduce the noise disturbance, the diesel engine has different correlation dimension in different conditions, this method can be effectively applied to the fault diagnosis of diesel engine.